In the programming course of our engineering design degree tutorials are the focal point of learning. This is especially so since we employ a tinkering based educational approach, in which students explore, from the very beginning, the material by self-defined projects. The assignment defines ingredients to use and sets expectations, but students are free to set their own design goals. In this setting tutorials are an important place of feedback and learning, and we developed an online platform that supports tutors during tutorials. This paper reports on the educational philosophy and underpinnings, and results from applying the tool in two first-year courses.